Currently, a number of different systems for opening, closing, or otherwise changing the position of a movable barrier are known. Of these, some are mounted on a wall or a ceiling for moving a door or gate. Other systems, or barrier operators, may be mounted on or at a ground surface for moving the barrier.
When mounting a barrier operator on a ground surface, a support structure is provided for securing and supporting the operator. The operator typically has an arm, a chain, or some other device coupling the operator to the barrier, such as a swinging gate. The operator moves the arm, for instance, to apply a force to the large, often metal barrier that spans across a driveway or paved entrance. As every action has an equal and opposite reaction, the force applied by the operator to pull or push the gate will also be experienced by the operator itself. Accordingly, it is important that the structure to which the operator is mounted be soundly installed with the ground, and that the operator itself is soundly installed to the support structure.
The support structure to which the operator is mounted is commonly referred to as a pad and is formed of poured concrete. To install the support structure, a ground area is excavated to a depth, typically at least a foot and often thirty inches or more. This depth will vary based on local soil conditions and other factors such as the frost line depth for the region or locale. In particular, local building codes are consulted for determining the proper minimum depth.
The excavated area is then surrounded by a form rising above the ground level. Concrete is then poured into the excavated area and into the form so that a height of the pad formed is typically at least three inches above the ground level. As the operator is mounted on a top surface of the concrete pad, the pad height provides clearance above the ground so that shifting soil, standing or flowing water, or snow does not as easily enter or cover a bottom portion of the operator. In this manner, the anchoring members, such as bolts, that hold the operator in place on the pad do not continually reside in a moist environment which would otherwise lead to corrosion and, ultimately, failure.
The concrete pad receives the barrier operator on the top surface, typically secured thereto by bolts. The bolts may be pre-set in the poured concrete prior to curing, or bolt holes may be drilled later for receiving the expansion bolts.
In any event, the concrete pad must cure prior to mounting of the operator. Prior to curing, the concrete pad is not capable of supporting the operator. Therefore, if bolts are pre-set, a template must be used to suspend and position the bolts. Alternatively, a template must also be used to drill the bolt or anchor holes for mounting the operator at a later time.
The entire installation process requires an extended period of time and more than one visit to the installation site. At a first instance, the excavation, the building of the form, and the pouring of the concrete may occur on a single day. However, once the concrete has been poured, a period of time must be waited for the curing process. Depending on temperatures and other factors, this curing time can be several days. An installer must return to the site at a later date and perform the steps for installing the operator itself onto the pad.
The provision of the concrete pad, as described, presents additional problems. The entire size of the pad can be, for example, in the order of 36″ in height, 24″ long, and 28″ wide. Such a volume has a significant materials cost and requires an equally significant amount of labor to mix and pour.
Because of the pad size, the concrete is susceptible to failure itself. A block of such as size should be agitated as it is poured to ensure large gas pockets are not formed. Additionally, proper curing may be compromised by soil or weather conditions, and improper curing may result in the pad cracking.
Accordingly, there has been a need for improvements in mounting barrier operators on a ground surface.